Tesla’s biohazard defense button works extraordinarily well – if you need it

When Tesla CEO Elon Musk announced the new Model X all-electric SUV came equipped with a Bioweapon Defense Mode, a lot of people thought he was joking. He does that, after all.It turns out the button, which activates a special HEPA filter to protect against pollution, is not only a real feature in the falcon-winged seven-seater, but it actually works. Tesla put a Model X through the paces in a lab environment to see how well the bioweapon defense system functions, and the results were pretty stunning.

Most Tesla drivers probably won’t have a chance to put their biohazard defenses to the test in the real world, and that’s a good thing. Much like a car’s airbags, you’d rather not have to use them, but knowing they are there makes a big difference. To lend a little confidence to the HEPA filtration system’s desired effects, Tesla put a Model X in a bubble filled with incredibly dirty air, closed the doors, and engaged the magic button.

The car’s filtration system, which was modeled after those used in hospitals and in the space industry, is hundreds of times more efficient than a standard automotive filter. It also works insanely fast. In under two minutes, the Model X’s HEPA filtration system was able to scrub extreme levels of pollution and create a completely safe breathing environment inside the car’s cabin. Tesla started with 1,000 µg/m³ of PM2.5, which far exceeds the EPA’s “good” air quality index of 12 µg/m³, and within minutes, test engineers were able to remove their protective gas masks and breathe normally inside the bubble.

Tesla’s advanced air filtration system also cleans the air outside the car, which is something traditional filters just don’t do. The test revealed that the Bioweapon Defense Mode reduced PM2.5 levels outside the car by 40 percent. This means that, when traveling through areas of intense air pollution—such as in Beijing—Tesla drivers can engage the filtration system to improve the quality of the air they are breathing inside the car, as well as help clean the surrounding air, benefitting other drivers on the road.

Right now, the Bioweapon Defense Mode is only available on the Model X, but Tesla is adding it to Model S cars currently in production, and it’s entirely likely we’ll see this on all future Tesla models as well.